minor update again with slight hacksaw action to the stem. only 6cm lopped off.

and probably the most interesting update, for now, 10sp veloce lever actuating the dahon neos RD at 7sp with a minor cable adjustment, aka "b-routing". almost works flawlessly. indexes 6 cogs correctly, and the last cog needs the 8th click from the lever to work.

what's odd is the dahon RD is a low normal so it takes some relearning to shift in the correct direction.

right now I've ordered a speed FD hanger, vitesse RD and 38T inner ring to try and get this to a double setup. also on the list of things to do is building up an ultegra or 105 hub/CR18 rear wheel so I can put a 9sp cassette on it.

CMIIW, I think the aluminium (Mu, Vitesse) and steel (Boardwalk, Speed) frames have different seat tube OD and hence different sized FD hangers.

that's what I thought too, but the aluminum speed rear triangle looks like it's the same thing as the vitesse. According to thorusa, it's the placement and angle that's more important.

Dahons use 34mm seatposts with a shim to protect the frame from wearing out at the seatpost clamp. hopefully the FD hanger will fit the seat tube which is 40.1mm OD.
I'll find out soon enough since I have one on order.

I'll be sure to give the clamp diameter before attaching it to the frame.

i ran into a problem with the front derailleur that i bought. i thought the 31.8 will fit the dahon boardwalk but it is way too small. will this adapted from thor work on my dahon boardwalk ? and do i need a braze on instead of clamp ?

OK, to finalize, although I'm not done yet, in case anyone wants to ask if they can do this mod...

bar clamp = 25.4mm/1" - so you can use 1" drop bars in the stem. mine are nitto 135 rando bars.

seat tube = 40.1mm - use thorusa speed FD hanger. (measure first, my vitesse uses a very similar rear triangle to the speed, which is why this was possible). It's not pictured, but this does have about 20mm of fore-aft adjustment so you can line up the FD

BB length = 117.5 x 68mm or 113 x 68mm + 3mm spacer. the FD hanger sticks out quite far and a shorter BB won't work. It should be noted that 113mm axle using the spacer puts the NDS arm very close to the kick stand so if possible just use 117.5mm axle.

dahon neos RD = shimano 2:1 cable pull, low normal with somewhere around 23T~25T total capacity and max. 30T cog size. cheaper option is to use shimano barend shifters. a 53/39 with 11-23 will exceed the RD capacity, but provide a wider, yet closely spaced gearing range compared to 52 x 11-30. This thing is LOW NORMAL, aka rapid rise so your shifter will function in reverse. you can do b-routing for shifting 9sp shimano cassette with 10sp campy shifters

rear wheel = 7sp uses a shorter freehub body than found on 8/9/10, so you'll need a new 130mm x 406mm rear wheel if you want more than 7sp. I have an ultegra hub laced to sun CR-18 rim in the works.

brakes = use travel agents or V-drop levers if using drop bars.

the FD hanger provides a cable stop so you can just route the cable housing anyway you want. me, I just slinged it under.

NDS arm and cup not installed because the shop gave me the wrong cup size...
who mixes a 68mm cartridge BB with a 73mm cup?

Another Dual Crank Upgrade albeit to a 2007 Dahon Speed P8

I found this thread recently and thought I'd throw in my version of a dual crank upgrade, albeit to a Dahon 2007 Speed P8.

As you might be able to see from the photo, I added a $34.95 Sugino XD (triple) Tandem RH Rear 170mm Arm, sized for a 116mm bottom bracket, purchased from Amazon.com (I already owned the non-drive side arm); a $3.95 (no, that's not a misprint) 68 x 116mm square taper BB from Cambriabike.com, to replace the Dahon stock 60 x 103 bottom bracket; a 32t and a 48t Vuelta chain ring purchased from Amazon.com and mounted as the inner and middle chain rings on the triple Sugino crank; a Sram MRX Comp Shifter, Microfriction Front, Grip/Twist from Bicyclesupply.com for $11.69 (free shipping) to control the front derailleur (yes, it's made for a triple crank but it can shift only as far the 2nd or middle chain ring when adjusted properly); matching Jagwire cable housing and inner wire, also from Amazon.com, to connect the front derailleur the new left-side Sram shifter; and a Shimano Sora 9-speed Double Road Bicycle Front Derailleur - FD-3400, also from Amazon.com. I bought the front derailleur mount reluctantly from Thor after trying first to source it from another seller (I didn't need to use the 3mm BB spacer that comes with the mount). For those of you who are leery of using a $3.95 bottom bracket, Amazon.com sells an Origin8/Token Alloy Cartridge Bottom Bracket - 68 x 116 for about $33.00.

Oh yeah, I also added a handlebar from Nashbar.com that has a slight rise. The rear rack is a Bike Friday cro-moly fold-up rack modified to fit the Speed P8 (simply shorten the length of the flat stock that connects the rack to the seat stay braze-ons and drill new holes to fit). The wheels were rebuilt by Gaerlan.com to accommodate the additional weight of two Ortlieb panniers and a trunk bag. The rear derailleur is stock 2007 Dahon. The front rack is Dahon.

To the OP: Is there a trick to getting the bike to shift from the big to the small chainring without the chain sagging? I put an mtb triple on the front of my Dahon Speed D7. I only need to be able to shift from the big to the middle chainrings, so Thor's adapter would be fine. The problem is, when I put the chain on the middle ring by hand it sagged. The rear derailleur couldn't take up the slack so I took 6 links out of the chain and put it on the middle ring permanently.

The problem is, when I put the chain on the middle ring by hand it sagged. The rear derailleur couldn't take up the slack so I took 6 links out of the chain and put it on the middle ring permanently.

If you exceeded the chain wrap capacity of the Neos Derailleur, you would need to mount a conventional medium or long cage r/d (depending on how much chain you needed to handle) .. an adapter plate to move the new r/d aft would be needed .. something like this could probably be made to work .

If you exceeded the chain wrap capacity of the Neos Derailleur, you would need to mount a conventional medium or long cage r/d (depending on how much chain you needed to handle) .. an adapter plate to move the new r/d aft would be needed .. something like this could probably be made to work .

To the OP: Is there a trick to getting the bike to shift from the big to the small chainring without the chain sagging? As you can see from this pic, I put an mtb triple on the front of my Dahon Speed D7. I only need to be able to shift from the big to the middle chainrings, so Thor's adapter would be fine. The problem is, when I put the chain on the middle ring by hand it sagged. The rear derailleur couldn't take up the slack so I took 6 links out of the chain and put it on the middle ring permanently.

no, not really.
at least, not with the dahon neos RD.

The largest teeth difference a dahon neos RD will accept is (53-39)+(23-12)=25T
it sags with a 26T difference, but honestly, you would have to cross chain quite badly for the chain to sag.

You will need to use a different RD entirely if you don't want any chance of chain sag with the above options.

minor update again with slight hacksaw action to the stem. only 6cm lopped off.

and probably the most interesting update, for now, 10sp veloce lever actuating the dahon neos RD at 7sp with a minor cable adjustment, aka "b-routing". almost works flawlessly. indexes 6 cogs correctly, and the last cog needs the 8th click from the lever to work.

what's odd is the dahon RD is a low normal so it takes some relearning to shift in the correct direction.

right now I've ordered a speed FD hanger, vitesse RD and 38T inner ring to try and get this to a double setup. also on the list of things to do is building up an ultegra or 105 hub/CR18 rear wheel so I can put a 9sp cassette on it.